Enhanced piezoelectric response in nanoclay induced electrospun PVDF nanofibers for energy harvesting

Abstract

Templated nanofibers of poly(vinylidene fluoride) have been designed on top of two dimensional nanoclay platelets for energy harvesting application. Dimension of nanofiber has been varied using different nanoclay content prepared through optimized electrospinning. The alteration in structure (electroactive phase) and morphology has been worked out as a function of nanoclay concentration. Nearly 90% piezoelectric active phase has been stabilized in presence of minimum quantity of nanoclay. Hybrid nanofiber is found to be tougher (300%) and stiffer by design, which in turn suitable for device application. Unimorph using hybrid nanofiber exhibits power generation up to 100 ms against less than 50 ms tenure using pristine fiber. Device has been fabricated using various nanofibers and demonstrates very high output voltage (70 V) and power density (68 μW cm−2) from the device made of hybrid nanofiber. Various modes of body movements e.g. bending, twisting, walking, foot and finger tapping can generate considerable power using the hybrid device and are able to transform waste mechanical energy to useful electric power. Underlying mechanism of charge separation in template system has been revealed which explain the high conversion of energy using the hybrid device. © 2019 Elsevier Ltd